Results 1 to 10 of about 34,519 (239)
A Model of Polarisation Rotations in Blazars from Kink Instabilities in Relativistic Jets
Galaxies, 2017 This paper presents a simple model of polarisation rotation in optically thin relativistic jets of blazars. The model is based on the development of helical (kink) mode of current-driven instability.
Krzysztof Nalewajko
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Classification of unassociated fermi-LAT sources [PDF]
ITM Web of Conferences, 2022 The Large Area Telescope (LAT) on board NASA’s Fermi Gamma-ray Space telescope has detected 5788 sources in the 4FGL catalogue. Among them, 271 have been associated to pulsars, 3436 to blazars, and 1782 remain unassociated sources.
Meng Qiyu
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The Astrophysical Journal, 2023 Recent works have developed samples of blazars from among the Fermi Large Area Telescope unassociated sources via machine-learning comparisons with known blazar samples. Continued analysis of these new blazars tests the predictions of the blazar sequence
Stephen Kerby, Abraham D. Falcone
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X-ray Flux and Spectral Variability of the TeV Blazars Mrk 421 and PKS 2155-304
Galaxies, 2020 We reviewed X-ray flux and spectral variability properties studied to date by various X-ray satellites for Mrk 421 and PKS 2155-304, which are TeV emitting blazars. Mrk 421 and PKS 2155-304 are the most X-ray luminous blazars in the northern and southern
Alok C. Gupta
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Exploring TeV Candidates of Fermi Blazars through Machine Learning
The Astrophysical Journal, 2023 In this work, we make use of a supervised machine-learning algorithm based on Logistic Regression (LR) to select TeV blazar candidates from the 4FGL-DR2/4LAC-DR2, 3FHL, 3HSP, and 2BIGB catalogs.
J. T. Zhu +5 more
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Probing Neutrino Production in Blazars by Millimeter VLBI
Galaxies, 2023 The advancement of neutrino observatories has sparked a surge in multi-messenger astronomy. Multiple neutrino associations among blazars are reported while neutrino production sites are located within their central (sub)parsecs.
Yuri Y. Kovalev +3 more
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Searches for IceCube neutrinos from blazar flares using correlations with gamma-ray lightcurves [PDF]
EPJ Web of Conferences, 2019 Blazars have long been considered as accelerator candidates for cosmic rays. In such a scenario, hadronic interactions in the jet would produce neutrinos and gamma rays.
Raab Christoph +1 more
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X-ray Spectral Evolution of High Energy Peaked Blazars
Galaxies, 2020 The synchrotron hump of the high energy peaked blazars generally lies in the 0.1–10 keV range and such sources show extreme flux and spectral variability in X-ray bands. Various spectral studies showed that the X-ray spectra of high energy peaked blazars
Haritma Gaur
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Swift detection of all previously undetected blazars in a micro-wave flux-limited sample of WMAP foreground sources [PDF]
, 2007 Almost the totality of the bright foreground sources in the WMAP CMB maps are blazars, a class of sources that show usually also X-ray emission. However, 23 objects in a flux-limited sample of 140 blazars of the WMAP catalog (first year) were never ...
A. Cucchiara +52 more
core +2 more sources
General Physical Properties of Fermi Blazars
The Astrophysical Journal Supplement Series, 2023 We study the general physical properties of Fermi blazars using the Fermi fourth source catalog data (4FGL-DR2). The quasi-simultaneous multiwavelength data of Fermi blazars are fitted by using the one-zone leptonic model to obtain some physical ...
Yongyun Chen +8 more
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